Added features to control building with or without GUI, or use Edge engine on Windows.

Cargo.toml

@@ -18,7 +18,6 @@ rust-crypto = "^0.2"
 blakeout = "0.1.0"
 num_cpus = "1.13.0"
 byteorder = "1.3.2"
-web-view = { version = "0.7.3", features = [] }
 tinyfiledialogs = "3.3.10"
 serde = { version = "1.0.123", features = ["derive"] }
 serde_json = "1.0.42"
@@ -34,6 +33,9 @@ mio = { version = "0.7", features = ["os-poll", "net"] }
 # for DNS from hermes
 derive_more = "0.99.9"
 
+# Optional dependencies regulated by features
+web-view = { version = "0.7.3", features = [], optional = true }
+
 [target.'cfg(windows)'.dependencies]
 thread-priority = "0.2.1"
 winapi = { version = "0.3.7", features = ["impl-default", "wincon", "shellscalingapi"]}
@@ -58,4 +60,9 @@ opt-level = 2
 
 [package.metadata.winres]
 ProductName="ALFIS"
-FileDescription="Alternative Free Identity System"
+FileDescription="Alternative Free Identity System"
+
+[features]
+webgui = ["web-view"]
+edge = ["web-view/edge"]
+default = ["webgui"]